Fix TUI apps (mc, htop, vim) freezing in SSH terminal

- Remove LNM mode that corrupted cursor positioning for TUI programs
- Add render debouncing (~60fps) to prevent UI thread blocking
- Add data batching in terminal tab to reduce render calls
- Increase SSH recv buffer from 4KB to 64KB

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/ssh_client.py

@@ -114,7 +114,7 @@ class ShellSession:
         try:
             while self._running:
                 try:
-                    data = self._channel.recv(4096)
+                    data = self._channel.recv(65536)
                     if not data:
                         break
                     if self.on_data: